CN103138819A - A base station apparatus, a terminal apparatus, a integrated circuit, and a transmission and reception method - Google Patents

Abstract

Provided is a radio communication device which can separate propagation paths of antenna ports and improve a channel estimation accuracy even when using virtual antennas. The device includes: a mapping unit which maps a data signal after modulation to a virtual antenna and a virtual antenna; a phase inversion unit which inverts the phase of S0 transmitted from an antenna port in synchronization with a phase inversion unit between the odd-number slot and the even-number slot; the phase inversion unit which inverts the phase of R0 transmitted from the antenna port; a phase inversion unit which inverts the phase of S1 transmitted from an antenna port in synchronization with a phase inversion unit; and the phase inversion unit which inverts the phase of R1 transmitted from an antenna port.

Description

Base station apparatus, terminal installation, integrated circuit and sending and receiving methods

The application be that August 15, application number in 2008 are 200880103318.5 the applying date, denomination of invention divides an application for the application for a patent for invention of " radio communication device and wireless communications method ".

Technical field

The present invention relates to radio communication device and wireless communications method.

Background technology

In 3GPP-LTE, adopt OFDMA (Orthogonal Frequency Division Multiple Access, OFDM) as the communication mode of downgoing line.In 3GPP-LTE, radio communication base station device (being designated hereinafter simply as " base station ") uses the predetermined communication resource to send reference signal (Reference Signal:RS), and radio communication terminal device (being designated hereinafter simply as " terminal ") uses the reference signal that receives to carry out channel estimating and data are carried out demodulation (with reference to non-patent literature 1).

In addition, in the situation that the base station has a plurality of antenna ports (antenna port), diversity transmission can be carried out in the base station.On the other hand, for the signal that receive diversity correctly sends, terminal need to be known the state of antenna port group that being used for from the base station the send propagation path till the terminal.Therefore, all antenna ports that need to have from the base station, interference-free sends RS mutually.In order to realize this transmission, adopt following methods in 3GPP-LTE, that is, from each antenna port of base station, use that mutually different timing and carrier frequency send RS on time shaft and frequency axis.

In Figure 1A, expression with the structure of the base station (2Tx base station) of 2 antenna ports of 3GPP-LTE imagination, represents the RS sending method of 2Tx base station in Figure 1B.Similarly, in Fig. 2 A, expression with the structure of the base station (4Tx base station) of 4 antenna ports of 3GPP-LTE imagination, represents the RS sending method of 4Tx base station in Fig. 2 B.Wherein, in Figure 1B, Fig. 2 B, the longitudinal axis (frequency axis) unit is subcarrier, and transverse axis (time shaft) unit is the OFDM code element.In addition, a time slot is made of the 7OFDM code element.In addition, R0, R1, R2, R3 represent respectively from the RS of antenna port 0,1,2,3 (the 1st, the 2nd, the 3rd, the 4th antenna port) transmission.In addition, a piece that bold box is surrounded (be 12 subcarriers on the frequency axis direction, be the 7OFDM code element on time-axis direction) unit is called Resource Block (Resource Block:RB).According to Figure 1B and Fig. 2 B as can be known, in the 4Tx base station, be suppressed at Min. in order to send the spent expense of RS, reduced the frequency that sends RS from antenna port 2 (the 3rd antenna port), antenna port 3 (the 4th antenna port).

In addition, the 1Tx base station only sends RS with the resource of the R0 in the RS configuration of 2Tx base station.

As mentioned above, in the 4Tx base station, the frequency that sends RS from antenna port 2 and antenna port 3 is low.Thus, receive from the terminal of the RS of 4Tx base station and can't carry out the interpolation of the channel estimation value of antenna port 2 and antenna port 3 in 1RB, so the precision of channel estimation during high-speed mobile is greatly deteriorated.So when terminal high-speed moved, by antenna port 2 and the antenna port 3 that does not use the base station, thereby the fact that the SNR characteristic of terminal becomes good was identified (with reference to non-patent literature 2).

Thus, in the past, although the 4Tx base station has four antenna ports, when terminal high-speed moves, only used two antenna ports.

Perhaps, in the past, in order to effectively utilize four wireless transmission unit of 4Tx base station, as shown in Figure 3, the 4Tx base station is processed as the virtual 2Tx base station of the virtual-antenna 1 that comprises the virtual-antenna (Virtual Antenna) 0 that is made of antenna port 0 and antenna port 2 and be made of antenna port 1 and antenna port 3.But, in Fig. 3, for the unnecessary wave beam that suppresses virtual-antenna forms effect, antenna port 2 and antenna port 3 have been added CDD (Cyclic delay diversity, cyclic delay diversity) generation unit.

At this moment, if will be made as from the signal that the map unit of Fig. 3 is exported

${\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="HDA00002928515100091.png,HDA00002928515100161.png"\; state="\{\{state\}\}">s</figure-callout>}}_{2\mathrm{Tx}}=\left(\begin{array}{c}{s}_0\\ {\mathrm{<figure-callout\; id="1"\; label="s"\; filenames="HDA00002928515100091.png"\; state="\{\{state\}\}">s</figure-callout>}}_1\end{array}\right)$

, the signal y that sends from four antenna ports so _VirtualBecome

$y_{\mathrm{virtual}}=\mathrm{<figure-callout\; id="10"\; label="D"\; filenames="HDA00002928515100021.png,HDA00002928515100121.png"\; state="\{\{state\}\}">D</figure-callout>}\left(\begin{array}{c}10\\ 01\\ 10\\ 01\end{array}\right){\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="HDA00002928515100091.png,HDA00002928515100161.png"\; state="\{\{state\}\}">s</figure-callout>}}_{2\mathrm{Tx}}$

。Wherein, D means 4 * 4 the diagonal matrix of CDD.

[non-patent literature 1] 3GPP TS 36.213 V1.1.0 (ftp: //ftp.3gpp.org/TSG_RAN/WG1_RL1/TSGR1_49/Docs/R1-072633.zip)

[non-patent literature 2] Transmit Diversity Scheme for Control Channel in E-UTRA (ftp: //ftp.3gpp.org/TSG_RAN/WG1_RL1/TSGR1_49/Docs/R1-072423.zip)

Summary of the invention

Problem to be addressed by invention

But when using virtual-antenna as above, the base station sends identical RS from two antenna ports, so terminal can't be separated the propagation path of four antenna ports of base station.Therefore, terminal can't be known the propagation path state between each antenna port and terminal.Thus, cause optimizing space division multiplexing (Space division multiplexing:SDM), this space division multiplexing can be controlled four antenna ports Transmit weight separately by the base station and realize.This problem can cause larger impact to the terminal (being designated hereinafter simply as " low speed terminal ") that low speed moves especially.

In addition, terminal is until receive the antenna port number that BCH (Broadcast Channel, broadcast channel) signal from the base station is just known this base station.In 3GPP-LTE, because also mixing the 1Tx base station, only do not use the R0 that is sent effectively to carry out channel estimating so know that the terminal of the antenna port number of base station has only.Thus, also use antenna port 0 antenna port in addition to send the BCH signal if having the base station of a plurality of antenna ports, cause so the sending method of base station and the method for reseptance of terminal not to mate.Therefore, only use antenna port 0 to send the BCH signal if having the base station of a plurality of antenna ports, although the base station has a plurality of antenna ports so, can't carry out the diversity transmission of BCH signal.Thus, the coverage area of the data-signal that sends with separable sets is compared, and the coverage area of BCH signal is little.

The object of the invention is to, even provide when using virtual-antenna, the propagation path of separable a plurality of antenna ports still, thus can improve radio communication device and the wireless communications method of precision of channel estimation.

The scheme of dealing with problems

The structure that radio communication device of the present invention adopts comprises: virtual-antenna is formed by a plurality of antenna ports; And the counter-rotating unit, make any the sign-inverted from the reference signal that each port of described a plurality of antenna ports sends.

Wireless communications method of the present invention is used for comprising the radio communication device of the virtual-antenna that is formed by a plurality of antenna ports, makes any the sign-inverted from the reference signal of each port transmission of described a plurality of antenna ports.

Base station apparatus of the present invention comprises: transmitting element, from a plurality of antenna ports, send the 1st reference signal with a plurality of the 1st resource elements, and send 2nd reference signal different from described the 1st reference signal with a plurality of the 2nd resource elements of the number that is less than described a plurality of the 1st resource elements, use either party or described the 1st reference signal of described the 1st reference signal and described the 2nd reference signal and described the 2nd reference signal both, will whether carry out channel quality with terminal and measure the antenna port number that is associated and be set in described terminal.

Terminal installation of the present invention comprises: receiving element, receive the 1st reference signal of using a plurality of antenna ports to send from base station apparatus with the 1st resource element, and receive with the 2nd resource element of the number that is less than described a plurality of the 1st reference signals 2nd reference signal different from described the 1st reference signal of using a plurality of antenna ports to send from base station apparatus; And estimation unit, based on the antenna port number of setting for our device, use either party in both of described the 1st reference signal and described the 2nd reference signal to carry out channel quality estimation.

Sending method of the present invention comprises: forwarding step, from a plurality of antenna ports, send the 1st reference signal with a plurality of the 1st resource elements, and send 2nd reference signal different from described the 1st reference signal with a plurality of the 2nd resource elements of the number that is less than described a plurality of the 1st resource elements; And the setting step, use described the 1st reference signal and described the 2nd reference signal in both either party or both, will whether carry out channel quality with terminal and measure the antenna port number that is associated and be set in described terminal.

Method of reseptance of the present invention comprises: receiving step, receive the 1st reference signal of using a plurality of antenna ports to send from base station apparatus with the 1st resource element, and receive with the 2nd resource element of the number that is less than described a plurality of the 1st reference signals 2nd reference signal different from described the 1st reference signal of using a plurality of antenna ports to send from base station apparatus; And estimating step, based on the antenna port number of setting for terminal installation, use either party in both of described the 1st reference signal and described the 2nd reference signal to carry out channel quality estimation.

Integrated circuit of the present invention, it controls following the processing: from a plurality of antenna ports, send the 1st reference signal with a plurality of the 1st resource elements, and send 2nd reference signal different from described the 1st reference signal with a plurality of the 2nd resource elements of the number that is less than described a plurality of the 1st resource elements; And use described the 1st reference signal and described the 2nd reference signal in both either party or both, will whether carry out channel quality with terminal and measure the antenna port number that is associated and be set in described terminal.

Integrated circuit of the present invention, it controls following the processing: receive the 1st reference signal of using a plurality of antenna ports to send from base station apparatus with the 1st resource element, and receive 2nd reference signal different from described the 1st reference signal with the 2nd resource element of the number that is less than described a plurality of the 1st reference signals; And based on the antenna port number of setting for our device, use either party in both of described the 1st reference signal and described the 2nd reference signal to carry out channel quality estimation.

The effect of invention

According to the present invention, even when using virtual-antenna, the propagation path of separable a plurality of antenna ports still, thus can improve precision of channel estimation.

Description of drawings

Figure 1A means the block diagram of the structure of 2Tx base station in the past.

Figure 1B means the figure of the RS sending method in the past 2Tx base station.

Fig. 2 A means the block diagram of the structure of 4Tx base station in the past.

Fig. 2 B means the figure of the RS sending method in the past 4Tx base station.

Fig. 3 means the block diagram of the structure of virtual 2Tx base station in the past.

Fig. 4 means the block diagram (situation of the working as carrying out the virtual 2Tx base station that virtual-antenna sends) of structure of the base station of embodiment of the present invention 1.

Fig. 5 means the block diagram (situation of the working as carrying out the 4Tx base station that antenna port sends) of structure of the base station of embodiment of the present invention 1.

Fig. 6 means the figure of the RS configuration of embodiment of the present invention 1.

Fig. 7 means BCH in 3GPP-LTE and the figure of the configuration of SCH on time shaft.

Fig. 8 means the figure of the configuration on the frequency axis of control channel of data channel in 3GPP-LTE and BCH and SCH.

Fig. 9 means the block diagram of structure of the base station of embodiment of the present invention 2.

Figure 10 A means the figure (frequency band that does not comprise BCH) of the RS configuration of embodiment of the present invention 2.

Figure 10 B means the figure (frequency band that comprises BCH) of the RS configuration of embodiment of the present invention 2.

Figure 11 means the figure of the RS configuration in the past 1Tx base station.

Figure 12 means the block diagram (situation of the working as carrying out the virtual 4Tx base station that virtual-antenna sends) of structure of the base station of embodiments of the present invention 3.

Figure 13 means the block diagram (situation of the working as carrying out the 8Tx base station that antenna port sends) of structure of the base station of embodiments of the present invention 3.

Figure 14 means the figure of the RS configuration of embodiment of the present invention 3.

Embodiment

Below, the execution mode that present invention will be described in detail with reference to the accompanying.

(execution mode 1)

In the present embodiment, the 4Tx base station uses two virtual-antennas that formed by two antenna ports respectively to send RS and data-signal (virtual-antenna transmission).But, the symbol that makes the signal that sends from any antenna port that forms a virtual-antenna on time shaft to each RB counter-rotating.

The base station is used virtual-antenna in this wise, thereby can effectively utilize four antenna ports, can optimize the transmission quality to high speed mobile terminal (being designated hereinafter simply as " high-speed terminal ") signal transmission simultaneously.In addition, because terminal can be separated into the RS from two virtual-antennas the RS from four antenna ports, terminal can be carried out the channel estimating of all antenna ports.

In addition, in the present embodiment, use four antenna ports to send the terminal of data-signal for being suitable for, particularly for low speed terminal, the base station is not used virtual-antenna but is used four antenna ports to send data-signal (antenna port transmission).But, comparatively it is desirable to, at antenna port 2 and antenna port 3, send data-signal by additional CDD generation unit when forming virtual-antenna.

Thus, wish that the terminal that virtual-antenna sends can coexist in the residential quarter of base station covering with wishing the terminal that antenna port sends.

In addition, in the present embodiment, the symbol that the base station also can make virtual-antenna sends RS and data-signal simultaneously on frequency axis but not reverse on time shaft.

Thus, terminal can make channel estimation value equalization on (before separating) time shaft of obtaining according to RS, therefore can improve the precision of channel estimation of terminal.

In addition, in the present embodiment, as long as no the request that comes self terminal, the 4Tx base station just continues to carry out virtual-antenna and sends as virtual 2Tx base station.That is, the 4Tx base station sends virtual-antenna according to the request that comes self terminal and switches to the antenna port transmission.So, in the present embodiment, the basic sending method of base station is made as virtual-antenna sends.Thus, can provide base station based on 3GPP-LTE.

Below, the base station 100 of detailed description present embodiment.Wherein, 100 the periphery in the base station, the 2Tx base station is can not make the distance that produces the degree of disturbing between the residential quarter exist.Due to terminal can be in the base station moving between cells of 100 residential quarter and 2Tx base station, so this terminal needs and can seamlessly communicate with any base station.

In addition, base station 100 conduct is usually carried out the virtual 2Tx base station of virtual-antenna transmission and is worked, but for the terminal of asking antenna port to send, work as the 4Tx base station of carrying out the antenna port transmission in this base station 100.

The structure of the base station 100 that in Fig. 4, expression is worked as the virtual 2Tx base station of carrying out the virtual-antenna transmission.

In base station shown in Figure 4 100,101 pairs of coding units send data and encode.

Data after 102 pairs of codings of modulating unit are modulated.

Data-signal after map unit 103 will be modulated is mapped to respectively virtual-antenna 0 and virtual-antenna 1.The data-signal that is mapped to virtual-antenna 0 is S ₀, the data-signal that is mapped to virtual-antenna 1 is S ₁In addition, the RS that sends from virtual-antenna 0 is R0, and the RS that sends from virtual-antenna 1 is R1.

Synchronizeing with the unit 105 that reverses in counter-rotating unit 104, makes the S that sends from antenna port 2 ₀Symbol reverse between odd number time slot and even number time slot.

Synchronizeing with counter-rotating unit 104 in counter-rotating unit 105, makes from the symbol of the R0 of antenna port 2 transmissions to reverse between odd number time slot and even number time slot.

106 pairs of IFFT unit (Inverse Fast Fourier Transform, inverse fast Fourier transform) S ₀And R0 carries out IFFT and generates the OFDM code element.

CP (Cyclic Prefix, Cyclic Prefix) extra cell 107 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 108 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 0.

CDD generation unit 109 is for S ₀And R0 generates CDD.

110 pairs of IFFT unit S ₀And R0 carries out IFFT and generates the OFDM code element.

CP extra cell 111 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 112 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 2.

Synchronizeing with the unit 114 that reverses in counter-rotating unit 113, makes the S that sends from antenna port 3 ₁Symbol reverse between odd number time slot and even number time slot.

Synchronizeing with counter-rotating unit 113 in counter-rotating unit 114, makes from the symbol of the R1 of antenna port 3 transmissions to reverse between odd number time slot and even number time slot.

115 pairs of IFFT unit S ₁And R1 carries out IFFT and generates the OFDM code element.

CP extra cell 116 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 117 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 1.

CDD generation unit 118 is for S ₁And R1 generates CDD.

119 pairs of IFFT unit S ₁And R1 carries out IFFT and generates the OFDM code element.

CP extra cell 120 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 121 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 3.

In addition, CDD generation unit 109,118 is set, forms effect in order to suppress the unnecessary wave beam of virtual-antenna.

The structure of the base station 100 that next, in Fig. 5, expression is worked as the 4Tx base station of carrying out the antenna port transmission.Base station 100 shown in Figure 5 does not comprise counter-rotating shown in Figure 4 unit 104,113.Below, the difference of key diagram 5 and Fig. 4 only.

That is the data-signal after, map unit 103 will be modulated is mapped to respectively antenna port 0,2,1,3.The data-signal that is mapped to antenna port 0 is S ₀, the data-signal that is mapped to antenna port 2 is S ₁, the data-signal that is mapped to antenna port 1 is S ₂, the data-signal that is mapped to antenna port 3 is S ₃In addition, the RS that sends from antenna port 0 and antenna port 2 is R0, and the RS that sends from antenna port 1 and antenna port 3 is R1.

CDD generation unit 109 is for S ₁And R0 generates CDD.

110 pairs of IFFT unit S ₁And R0 carries out IFFT and generates the OFDM code element.

115 pairs of IFFT unit S ₂And R1 carries out IFFT and generates the OFDM code element.

CDD generation unit 118 is for S ₃And R1 generates CDD.

119 pairs of IFFT unit S ₃And R1 carries out IFFT and generates the OFDM code element.

Here, base station 100 shown in Figure 4 (virtual 2Tx base station) uses two virtual-antennas of virtual-antenna 0 and virtual-antenna 1 to send RS and data-signal.That is, the basic sending method with base station 100 is made as the virtual-antenna transmission.

But, between odd number time slot and even number time slot, make the sign-inverted of the signal of any antenna port in two antenna ports that form a virtual-antenna.In Fig. 4, make the antenna port 0 of formation virtual-antenna 0 and R0 and the S of the antenna port 2 in antenna port 2 ₀Symbol reverse between odd number time slot and even number time slot.Similarly, make the antenna port 1 of formation virtual-antenna 1 and R1 and the S of the antenna port 3 in antenna port 3 ₁Symbol reverse between odd number time slot and even number time slot.

Because work as virtual 2Tx base station usually in base station 100, thus from the RS of base station 100 with from the identical resource (identical timing and same subcarrier) of the RS of the 2Tx base station that is present in base station 100 peripheries and be sent out.The configuration of expression RS at this moment in Fig. 6.But the R0 ' expression in Fig. 6 sends the resource (timing and frequency) of R0, R0 from antenna port 0 and antenna port 2 " represent to send R0 and send from antenna port 2 resource that the symbol that makes R0 has carried out the RS of counter-rotating gained from antenna port 0.Similarly, the R1 ' expression in Fig. 6 sends the resource of R1, R1 from antenna port 1 and antenna port 3 " represent to send R1 and send from antenna port 3 resource that the symbol that makes R1 has carried out the RS of counter-rotating gained from antenna port 1.

Thus, from the following expression of transmitted signal y of base station 100 (virtual 2Tx base station).

$y=\mathrm{<figure-callout\; id="10"\; label="D"\; filenames="HDA00002928515100021.png,HDA00002928515100121.png"\; state="\{\{state\}\}">D</figure-callout>}\left(\begin{array}{c}10\\ 01\\ 10\\ 01\end{array}\right){\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="HDA00002928515100091.png,HDA00002928515100161.png"\; state="\{\{state\}\}">s</figure-callout>}}_{2\mathrm{Tx}}\mathrm{evenslot},$ $y=\mathrm{<figure-callout\; id="10"\; label="D"\; filenames="HDA00002928515100021.png,HDA00002928515100121.png"\; state="\{\{state\}\}">D</figure-callout>}\left(\begin{array}{c}10\\ 01\\ -10\\ 0-1\end{array}\right){\mathrm{<figure-callout\; id="2"\; label="s"\; filenames="HDA00002928515100091.png,HDA00002928515100161.png"\; state="\{\{state\}\}">s</figure-callout>}}_{2\mathrm{Tx}}\mathrm{oddslot}$

According to Fig. 6 as can be known, send in the present embodiment the required expense of RS identical with the 2Tx base station.That is, according to present embodiment, can not occur to reduce because expense increases the throughput that causes.

In addition, because each virtual-antenna can use two wireless transmission unit, so the transmitted power of the transmitted power of RS and data-signal is 2 times of corresponding transmitted power in the 2Tx base station.Thus, can improve the quality of reception in terminal.

And, for the RS in 1RB and data-signal, use identical virtual-antenna and work as virtual 2Tx base station, therefore, the SNR characteristic of high-speed terminal can variation.

Base station 100 for the both sides of high-speed terminal and low speed terminal similarly, uses virtual-antenna 0 and virtual-antenna 1 to send the both sides of RS and data-signal usually.

Terminal at first directly uses the RS that receives to carry out demodulation to data-signal.

In addition, the RS of two time slots on terminal holding time axle.The R0 ' that is saved by this way, R0 ", R1 ', R1 " between have relation shown below.

Reception signal in R0 '=from the signal of antenna port 0+from the signal of antenna port 2

Reception signal in R1 '=from the signal of antenna port 1+from the signal of antenna port 3

R0 " in reception signal=from the signal of antenna port 0-from the signal of antenna port 2

R1 " in reception signal=from the signal of antenna port 1-from the signal of antenna port 3

Thus, terminal can be separated from antenna port 0,2,1,3 signal by following calculating, and carries out the channel estimating of each antenna port.

From the reception signal+R0 in the signal=R0 ' of antenna port 0 " in the reception signal

From the reception signal-R0 in the signal=R0 ' of antenna port 2 " in the reception signal

From the reception signal+R1 in the signal=R1 ' of antenna port 1 " in the reception signal

From the reception signal-R1 in the signal=R1 ' of antenna port 3 " in the reception signal

Terminal is according to antenna port 0,2,1, four channel estimation values of 3, select virtual-antenna to send or antenna port any pattern in sending as the best sending method of 100 pairs of these terminals in base station, and selection result is fed back to base station 100 as the sending mode request.For example, can carry out SDM when the relevant low of antenna port 0,2,1, four propagation paths of 3 when sending, usually be preferably and do not carry out virtual-antenna and send, therefore select antenna port to send.But, because also comprise in antenna port 2,3 channel estimation results based on CDD generation unit 109,118 propagation characteristic, therefore, even send in the situation that antenna port is carried out by structure shown in Figure 5 in base station 100, still can use the identical CDD generation unit of CDD generation unit that when sending with virtual-antenna, (Fig. 4) uses.

In addition, be no matter that virtual-antenna sends (Fig. 4), or send (Fig. 5) at antenna port, base station 100 all makes antenna port 2,3 sign-inverted, lasting transmission RS on one side on one side.

Here, if will be made as from the output of the map unit 103 in base station shown in Figure 5 100 (4Tx base station)

${\mathrm{<figure-callout\; id="4"\; label="s"\; filenames="HDA00002928515100091.png"\; state="\{\{state\}\}">s</figure-callout>}}_{4\mathrm{Tx}}=\left(\begin{array}{c}{s}_0\\ s_1\\ s_2\\ {\mathrm{<figure-callout\; id="3"\; label="s"\; filenames="HDA00002928515100091.png"\; state="\{\{state\}\}">s</figure-callout>}}_3\end{array}\right)$

, the signal y that sends from four antenna ports so _RealportBecome

y _realport＝Ds _4Tx。

Select the virtual-antenna terminal that sends and the terminal of selecting antenna port to send to be re-used by OFDM, therefore, base station 100 sends (Fig. 4) to each terminal switching virtual antenna and sends (Fig. 5) with antenna port according to the request from each terminal.Namely, base station 100 has switch unit, this switch unit is according to the request from each terminal, each terminal switching virtual antenna is sent (Fig. 4) send (Fig. 5) with antenna port, low speed terminal for the transmission of request virtual-antenna, by structure shown in Figure 4, send RS and data-signal with the virtual-antenna sending mode; Low speed terminal for the request antenna port sends by structure shown in Figure 5, sends data-signal with the antenna port sending mode.

When carrying out the virtual-antenna transmission, each terminal directly uses RS to carry out channel estimating.On the other hand, when carrying out the antenna port transmission, each terminal is separated RS to each antenna port, uses the RS after separating to carry out channel estimating.

Here, 100 request virtual-antennas send the terminal that high-speed terminal or do not support sends based on the antenna port of 4 antenna ports to the base station, and 100 request antenna ports send and get final product the terminal that low speed terminal maybe can carry out SDM to the base station.

In addition, terminal also can be when any sending mode in base station 100 request pseudo channel antennas transmissions or antenna port transmission, the mapping (PrecodingMatrix, pre-coding matrix) of 100 request change data-signals to the base station simultaneously.

In the situation that base station 100 requested the pseudo channel antenna send, as shown in Figure 4, carry out two antenna ports to virtual-antenna with after mapping, then carry out the distribution to four antenna ports in virtual-antenna.Therefore, although the antenna port number of base station 100 is four, the optimum mapping pattern in a plurality of mapping patterns (pattern) that terminal is used to base station 100 request two antenna ports.

On the other hand, 100 request antenna ports send in the situation that terminal is to the base station, the optimum mapping pattern in its a plurality of mapping patterns of using to base station 100 request 4 antenna ports.

According to present embodiment, compare with 4Tx base station in the past, can reduce sending the required expense of RS.In addition, because from density (aggregate power) height of antenna port 2,3 RS, so can improve the precision of channel estimation of terminal.In addition, send by using virtual-antenna, can increase radius of society.And, because terminal in the future the RS of self-virtualizing antenna be separated into the RS of each antenna port, so can carry out to the base station requests base station the best sending method of SDM when sending.

In addition, in the present embodiment, illustrated that imagination when terminal receives signal from the base station 100 (Fig. 4) of working as virtual 2Tx base station, carries out independently channel estimating to each time slot, and to the situation of the symbol of each time slot change virtual-antenna.But, for example in the situation that terminal is carried out channel estimating to every n time slot, also can change to every n time slot the symbol of virtual-antenna.

In addition, the base station 100 in Fig. 4 and Fig. 5 also can not be equipped with CDD generation unit 109,118.

In addition, in the present embodiment, the characteristic of virtual-antenna is made as

$\mathrm{<figure-callout\; id="10"\; label="D"\; filenames="HDA00002928515100021.png,HDA00002928515100121.png"\; state="\{\{state\}\}">D</figure-callout>}\left(\begin{array}{c}10\\ 01\\ 10\\ 01\end{array}\right)\mathrm{evenslot},$ $\mathrm{<figure-callout\; id="10"\; label="D"\; filenames="HDA00002928515100021.png,HDA00002928515100121.png"\; state="\{\{state\}\}">D</figure-callout>}\left(\begin{array}{c}10\\ 01\\ -10\\ 0-1\end{array}\right)\mathrm{oddslot}$

。But, for example also can use the virtual-antenna with following characteristic.

$\mathrm{<figure-callout\; id="10"\; label="D"\; filenames="HDA00002928515100021.png,HDA00002928515100121.png"\; state="\{\{state\}\}">D</figure-callout>}\left(\begin{array}{c}10\\ 10\\ 01\\ 01\end{array}\right)\mathrm{evenslot},$ $D\left(\begin{array}{c}10\\ -10\\ 01\\ 0-1\end{array}\right)\mathrm{oddslot}$

In the case, terminal is separated from antenna port 0,1,2,3 signal by following calculating.

From the reception signal+R0 in the signal=R0 ' of antenna port 0 " in the reception signal

From the reception signal-R0 in the signal=R0 ' of antenna port 1 " in the reception signal

From the reception signal+R1 in the signal=R1 ' of antenna port 2 " in the reception signal

From the reception signal-R1 in the signal=R1 ' of antenna port 3 " in the reception signal

That is, when in even number time slot and odd number time slot, from 4 * 2 the above-mentioned matrix of the characteristic of expression virtual-antenna, when having taken out respectively two vectors that consisted of by the row component, four mutually orthogonal getting final product of vector of the total of taking out.More generally, signal that also can multiplexing each antenna port makes terminal can use the RS that repeatedly receives, and separates reaching in the same time mutually the propagation path that same frequency comes a plurality of antenna ports of transmitted signal.

In addition, in the present embodiment, every time slot is changed the symbol of (counter-rotating) virtual-antenna on time shaft, on the other hand the fixing symbol on the frequency axis of virtual-antenna.But, also can be on frequency axis every RB be changed the symbol of (counter-rotating) virtual-antenna, on the other hand the fixing symbol on the time shaft of virtual-antenna.In this case, because do not change on time shaft in order to the characteristic of the virtual-antenna that sends RS, so can average by the RS that terminal is received, improve the precision of channel estimation of terminal in the multi-slot scope.But, in this case for the tolerance step-down of frequency selective fading, therefore, also can be according to the state of propagation path, the pattern that switches in adaptively the pattern of the symbol that changes virtual-antenna on time shaft and change the symbol of virtual-antenna on frequency axis.

In addition, in the present embodiment, illustrated that the base station utilizes two antenna ports to form the situation of a virtual-antenna.But in the present invention, the antenna port number that forms a virtual-antenna is not limited to two.For example, the base station also can utilize four antenna ports to form a virtual-antenna.But, terminal is in order to separate the propagation path of each antenna port, in the situation that utilize two antenna ports to form a virtual-antenna to need the RS of two time slots (for example R0 ' shown in Figure 6 and R0 "), and in the situation that utilize four antenna ports to form the RS that a virtual-antenna needs 4 time slots.For example, utilize four antenna ports to form the base station of a virtual-antenna, be sent on time shaft to each time slot change R0 ', the R0 ", R0 " of the symbol of virtual-antenna ', R0 " ".Terminal use R0 ', R0 ", R0 " ', R0 " " separates the signal of each antenna port, and carries out the channel estimating of each antenna port.

In addition, the base station also can be according to the situation of terminal, and adaptively modifying forms the antenna port number of a virtual-antenna.Namely, in the situation that the base station has four antenna ports, the action that utilizes two antenna ports to form the action of a virtual-antenna and utilize a virtual-antenna of four antenna ports formation also can be switched according to the situation of terminal in the base station as shown in present embodiment.

For example, the change of the propagation path in the situation that terminal high-speed moves on time-axis direction is violent, and during four RS of time-axis direction transmission, the state of propagation path changes sometimes, and terminal is separation signal correctly.Therefore, the antenna port number that forms virtual-antenna also can be switched according to the translational speed of terminal in the base station.For example, for high speed mobile terminal, the base station utilizes two antenna ports to form a virtual-antenna, and two RS ' after reindexing are configured in two time slots.On the other hand, for the low speed mobile terminal, the base station utilizes four antenna ports to form a virtual-antenna, and four RS after reindexing are configured in four time slots.Thus, the expense of RS Min. can be suppressed at, the best utilization corresponding to the translational speed of terminal can be realized simultaneously.

(execution mode 2)

The difference of present embodiment and execution mode 1 is, at the BCH that is used for notice antenna port number, the mode that always sends with virtual-antenna sends RS and BCH signal.

Thus, according to present embodiment, regardless of the antenna port number of base station, terminal all can obtain diversity effect in BCH.In addition, terminal is carried out channel estimating by the propagation path that separates two antenna ports, thereby terminal can be optimized the Transmit weight of base station after receiving the BCH signal.

Here, repeatedly send the BCH signal with identical information in BCH.In addition, the BCH signal always takies partial-band and is continued to send.And the BCH signal is received by all terminals.In addition, when terminal received the BCH signal, the antenna port number of base station was unknown.

Therefore, in the present embodiment, do not rely on antenna port number ground and carry out common RS configuration, thereby reduce the reception load of terminal, obtain and the equal diversity gain of SFBC (Space-frequency block coding, space frequency block coding) simultaneously.

The following describes the transmission of the BCH signal of present embodiment.

In the program of 3GPP-LTE, when terminal begins to communicate by letter with the base station, catch SCH (Synchronization Channel, synchronizing channel) and with the timing of base station set up synchronize after, receive the BCH signal.BCH and the configuration of SCH on time shaft in Fig. 7 in expression 3GPP-LTE.A time slot in Fig. 7 is equivalent to the time of 1RB.

In addition, the data channel in expression 3GPP-LTE and the configuration of control channel on frequency axis of BCH and SCH in Fig. 8.These control channel signals use 72 subcarriers=6RB to send from the base station.

When the 2Tx base station of present embodiment sends RS, BCH signal and SCH signal in the frequency band that comprises BCH and SCH shown in Figure 8, two antenna ports are considered as a virtual-antenna.But, on time shaft, each RB is made sign-inverted from the signal of antenna port 1.In addition, in the frequency band that does not comprise BCH and SCH, work as common 2Tx base station (Figure 1A).

The structure of the base station 200 of expression present embodiment in Fig. 9.

In base station shown in Figure 9 200,201 pairs of coding units send data (data channel) and encode.

Data after 202 pairs of codings of modulating unit are modulated.

Data-signal after map unit 203 will be modulated is mapped to respectively antenna port 0 and antenna port 1.The data-signal that is mapped to antenna port 0 is S ₀, the data-signal that is mapped to antenna port 1 is S ₁In addition, be additional to S ₀And be R0 from the RS of antenna port 0 transmission, be additional to S ₁And the RS that sends from antenna port 1 is R1.

On the other hand, 204 pairs of BCH data of coding unit (BCH) are encoded.

BCH data after 205 pairs of codings of modulating unit are modulated.

BCH data-signal after map unit 206 will be modulated is mapped to by antenna port 0 and the formed virtual-antenna 0 of antenna port 1.The BCH data-signal that is mapped to virtual-antenna 0 is B ₀

Counter-rotating unit 207 synchronously makes with the unit 208 that reverses the B that sends from antenna port 0 ₀Symbol reverse between odd number time slot and even number time slot.

Counter-rotating unit 208 synchronously makes with the unit 207 that reverses and is additional to B ₀And the symbol of the R0 that sends from antenna port 0 reverses between odd number time slot and even number time slot.

CDD generation unit 209 is for B ₀And R0 generates CDD.

210 pairs of IFFT unit S ₀, R0 and B ₀, R0 carries out IFFT and generates the OFDM code element.

CP extra cell 211 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 212 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 0.

213 pairs of IFFT unit S ₁, R1 and B ₀, R0 carries out IFFT and generates the OFDM code element.

CP extra cell 214 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 215 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 1.

Like this, antenna port 0 and antenna port 1 have the function of virtual-antenna 0 in BCH.

In addition, CDD generation unit 209 is set, forms effect in order to suppress the unnecessary wave beam of virtual-antenna.

Next, the configuration of the RS of expression present embodiment in Figure 10 A and Figure 10 B.The frequency band that Figure 10 A represents not comprise BCH is the RS configuration in the frequency band of data channel, and Figure 10 B represents to comprise the RS configuration in the frequency band of BCH.In addition, the RS configuration in expression 1Tx base station in the past in Figure 11.Have, the R0 ' expression in Figure 10 B sends the resource of R0, R0 from antenna port 0 and antenna port 1 again " represent to send R0 and send from antenna port 1 resource that the symbol that makes R0 has carried out the RS of counter-rotating gained from antenna port 0.

Like this, in base station 200, make RS configuration (Figure 10 B) and RS in the 1Tx base station in the frequency band that comprises BCH configure (Figure 11) identical.

To this, terminal receives the SCH (Fig. 7) that sends from the base station and catches synchronous.Because this SCH known sequence that is terminal, thus the known SCH sequence that terminal can be by asking pre-save with receive cross-correlation between burst and catch and synchronize.In addition, SCH is also similarly sent by virtual-antenna with BCH.

Terminal receives R0 ' or R0 after catching synchronously " and carry out channel estimating, the BCH sequence is decoded.

Here, in base station 200, the symbol that makes BCH and sign synchronization in order to the virtual-antenna that sends R0 ' (or R0 ").Thus, terminal to need not differentiate to receive signal be R0 ' or R0 ".

And, in Fig. 7, base station 200 makes the sign-inverted of symbol with the virtual-antenna that uses of the virtual-antenna that uses in the 1st time slot of the 1st subframe in the 1st time slot of the 6th subframe, therefore, even in the zone that BCH and SCH can't arrive usually, still can receive BCH and SCH by diversity effect.

Terminal judges the antenna port number of base station based on the BCH data after receiving BCH, and according to the RS sending method in the frequency band of these antenna port number judgement transmission data.

According to present embodiment, in the communication system that is mixing 1Tx base station and 2Tx base station, terminal can be by the common method of reseptance reception BCH in 1Tx base station and 2Tx base station.Thus, even terminal is not known the antenna port number of base station, still can correctly receive BCH.That is, can realize the diversity transmission of 2Tx base station in BCH.

In addition, if by same method in the past, two antenna ports are processed as a virtual-antenna and sent BCH, RS is also sent by virtual-antenna so, and therefore, terminal can't be separated the propagation path of two antenna ports.To this, in the present embodiment, because the base station sends RS in the symbol that changes (counter-rotating) virtual-antenna, so terminal can be separated the propagation path of two antenna ports.

In addition, in the present embodiment, will use the frequency band of virtual-antenna to be defined as the partial-band that comprises BCH.Thus, in the frequency band that does not use virtual-antenna (for example, the frequency band of data channel), average on time shaft by the RS that terminal is received, can improve precision of channel estimation.

In addition, according to present embodiment, in the communication system that is mixing the different a plurality of base stations of antenna port number, when realizing common RS configuration, terminal can be enjoyed the diversity effect of each base station, so can improve the design freedom of communication system.

In addition, also can similarly carry out with the above-mentioned transmission of BCH the transmission of BCH control information in addition.

In addition, send in the situation that SCH also similarly carries out virtual-antenna with BCH, comparatively it is desirable to, only generate CDD and SCH is not generated CDD for BCH.Thus, do not exist the extra time of advent that is caused by CDD poor between a plurality of antenna ports, therefore can improve the performance of the synchronization acquistion of using SCH.

In addition, as the diversity effect under relatively the BCH transmission of present embodiment sends with the BCH that has used SFBC, result is as described below.Here, the transmitting antenna port number of base station is made as 2, the reception antenna port number of terminal is made as 1, the characteristic of the propagation path till will be from the antenna port 0 of base station to the antenna port of terminal is made as h ₀The characteristic of the propagation path till (f), will be from the antenna port 1 of base station to the antenna port of terminal is made as h ₁(f).

In the BCH that has used SFBC sent, the received power of terminal was

$\underset{f}{\mathrm{\&Sigma;}}\{{\mathrm{<figure-callout\; id="0"\; label="h"\; filenames="HDA00002928515100041.png,HDA00002928515100081.png"\; state="\{\{state\}\}">h</figure-callout>}}_0^2\left(f\right)+{\mathrm{<figure-callout\; id="1"\; label="h"\; filenames="HDA00002928515100091.png"\; state="\{\{state\}\}">h</figure-callout>}}_1^2\left(f\right)\}.$

On the other hand, in the BCH of present embodiment sent, the received power of terminal was

$\underset{f}{\mathrm{\&Sigma;}}{\{h_0\left(f\right)+e^{-\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="HDA00002928515100091.png,HDA00002928515100161.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;f\&delta;}}{h}_1\left(f\right)\}}^2...\mathrm{evenslot},$ $\underset{f}{\mathrm{\&Sigma;}}{\{h_0\left(f\right)-e^{-\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="HDA00002928515100091.png,HDA00002928515100161.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;f\&delta;}}{h}_1\left(f\right)\}}^2...\mathrm{oddslot}$

。Wherein, e ^{-j2 π f δ}Component for CDD.

Thus, according to present embodiment, the mean receiving power of the BCH in terminal is

$\frac{\underset{f}{\mathrm{\&Sigma;}}{\{h_0\left(f\right)+e^{-\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="HDA00002928515100091.png,HDA00002928515100161.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;f\&delta;}}{h}_1\left(f\right)\}}^2+\underset{f}{\mathrm{\&Sigma;}}{\{h_0\left(f\right)-e^{-\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="HDA00002928515100091.png,HDA00002928515100161.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;f\&delta;}}{h}_1\left(f\right)\}}^2}{2}=\underset{f}{\mathrm{\&Sigma;}}\{{\mathrm{<figure-callout\; id="0"\; label="h"\; filenames="HDA00002928515100041.png,HDA00002928515100081.png"\; state="\{\{state\}\}">h</figure-callout>}}_0^2\left(f\right)+{\left|e^{-\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="HDA00002928515100091.png,HDA00002928515100161.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;f\&delta;}}\right|}^2{\mathrm{<figure-callout\; id="1"\; label="h"\; filenames="HDA00002928515100091.png"\; state="\{\{state\}\}">h</figure-callout>}}_1^2\left(f\right)\}=\underset{f}{\mathrm{\&Sigma;}}\{{\mathrm{<figure-callout\; id="0"\; label="h"\; filenames="HDA00002928515100041.png,HDA00002928515100081.png"\; state="\{\{state\}\}">h</figure-callout>}}_0^2\left(f\right)+{\mathrm{<figure-callout\; id="1"\; label="h"\; filenames="HDA00002928515100091.png"\; state="\{\{state\}\}">h</figure-callout>}}_1^2\left(f\right)\}$

, it equates with the mean receiving power of SFBC.

In addition, the maximal received power that the BCH of present embodiment sends, the maximal received power that sends greater than the BCH based on SFBC.Thus, according to the BCH transmission of present embodiment, can make the maximum of BCH arrive the maximum arrival distance that distance sends greater than the BCH based on SFBC.Thus, according to present embodiment, for the information that repeats to send repeatedly, can obtain to surpass the diversity effect of SFBC as BCH.

(execution mode 3)

The difference of present embodiment and execution mode 1 is to send data-signal by the base station of 8 antenna ports (8Tx base station).

The antenna port number of the base station in 3GPP-LTE is four to the maximum.Therefore, support the terminal of 3GPP-LTE can use the RS that has base station (4Tx base station) transmission of four antenna ports from maximum, carry out the demodulation of data and the quality determination of downstream signal.

To this, be in LTE-advanced in the evolution form of 3GPP-LTE, inquiring into maximum base station (8Tx base station) with eight antenna ports.But, for the terminal that makes the base station (4Tx base station) of only supporting 3GPP-LTE also can communicate, need to provide the base station based on 3GPP-LTE under LTE-advanced.In other words, in mixing the communication system of 4Tx base station (base station of 3GPP-LTE) and 8Tx base station (base station of LTE-advanced), the terminal (hereinafter referred to as " LTE terminal ") of only supporting the 4Tx base station supports also that with the terminal of not only supporting the 4Tx base station terminal (hereinafter referred to as " LTE+ the terminal ") needs of 8Tx base station can be with identical frequency bands for communication.

Therefore, the 8Tx base station in present embodiment is for the LTE terminal, uses respectively four the virtual-antennas transmission RS and the data-signal (virtual-antenna transmission) that are formed by two antenna ports.In addition, the 8Tx base station in present embodiment uses 8 antenna ports to send the LTE+ terminal of data-signals for being suitable for, and does not use virtual-antenna but uses eight antenna ports to send RS and data-signal (antenna port transmission).

But, antenna port is being carried out when sending in the 8Tx base station of present embodiment, make as the RS that only is disposed at the transmission frequency band that carries out the data-signal that antenna port sends, and any the sign-inverted from two RS that two antenna ports that form a virtual-antenna jointly send respectively.

The below describes the base station 300 of present embodiment in detail.

The structure of the base station 300 that in Figure 12, expression is worked as the virtual 4Tx base station of carrying out the virtual-antenna transmission.

In base station shown in Figure 12 300,301 pairs of coding units send data and encode.

Data after 302 pairs of codings of modulating unit are modulated.

Data-signal after map unit 303 will be modulated is mapped to respectively virtual-antenna 0, virtual-antenna 1, virtual-antenna 2 and virtual-antenna 3.The data-signal that is mapped to virtual-antenna 0 is S ₀, the data-signal that is mapped to virtual-antenna 1 is S ₁, the data-signal that is mapped to virtual-antenna 2 is S ₂, the data-signal that is mapped to virtual-antenna 3 is S ₃In addition, the RS that sends from virtual-antenna 0 is R0, and the RS that sends from virtual-antenna 1 is R1, and the RS that sends from virtual-antenna 2 is R2, and the RS that sends from virtual-antenna 3 is R3.

304 pairs of IFFT unit S ₀And R0 carries out IFFT and generates the OFDM code element.

CP extra cell 305 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 306 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 0.

CDD generation unit 307 is for S ₀And R0 generates CDD.

308 pairs of IFFT unit S ₀And R0 carries out IFFT and generates the OFDM code element.

CP extra cell 309 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 310 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 1.

311 pairs of IFFT unit S ₁And R1 carries out IFFT and generates the OFDM code element.

CP extra cell 312 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 313 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 2.

CDD generation unit 314 is for S ₁And R1 generates CDD.

315 pairs of IFFT unit S ₁And R1 carries out IFFT and generates the OFDM code element.

CP extra cell 316 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 317 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 3.

318 pairs of IFFT unit S ₂And R2 carries out IFFT and generates the OFDM code element.

CP extra cell 319 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 320 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 4.

CDD generation unit 321 is for S ₂And R2 generates CDD.

322 pairs of IFFT unit S ₂And R2 carries out IFFT and generates the OFDM code element.

CP extra cell 323 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 324 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 5.

325 pairs of IFFT unit S ₃And R3 carries out IFFT and generates the OFDM code element.

CP extra cell 326 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 327 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 6.

CDD generation unit 328 is for S ₃And R3 generates CDD.

329 pairs of IFFT unit S ₃And R3 carries out IFFT and generates the OFDM code element.

CP extra cell 330 appends to the front end of OFDM code element with the signal identical with the rear end part of OFDM code element as CP.

OFDM code element after the additional CP in 331 pairs of wireless transmission unit is carried out the transmission processing such as D/A conversion, amplification and up-conversion and is sent from antenna port 7.

In addition, CDD generation unit 307,314,321,328 is set, forms effect in order to suppress the unnecessary wave beam of virtual-antenna.

The structure of the base station 300 that next, in Figure 13, expression is worked as the 8Tx base station of carrying out the antenna port transmission.The below only illustrates the difference of Figure 13 and Figure 12.

That is the data-signal S after, map unit 303 will be modulated ₀～S ₇Be mapped to respectively antenna port 0～7.In addition, be R0 and R4 from the RS of antenna port 0 and antenna port 1 transmission, the RS that sends from antenna port 2 and antenna port 3 is R1 and R5, and the RS that sends from antenna port 4 and antenna port 5 is R2 and R6, and the RS that sends from antenna port 6 and antenna port 7 is R3 and R7.That is, the base station 300 (8Tx base station) of carrying out the antenna port transmission has sent RS with virtual-antenna send mode shown in Figure 12 except sending, and also sends R4～R7.

304 pairs of IFFT unit S ₀, R0 and R4 carry out IFFT and generate the OFDM code element.

Counter-rotating unit 332 makes from the sign-inverted of the R4 of antenna port 1 transmission.

CDD generation unit 307 is for S ₁, R0 and R4 generate CDD.

308 pairs of IFFT unit S ₁, R0 and R4 carry out IFFT and generate the OFDM code element.

311 pairs of IFFT unit S ₂, R1 and R5 carry out IFFT and generate the OFDM code element.

Counter-rotating unit 333 makes from the sign-inverted of the R5 of antenna port 3 transmissions.

CDD generation unit 314 is for S ₃, R1 and R5 generate CDD.

315 pairs of IFFT unit S ₃, R1 and R5 carry out IFFT and generate the OFDM code element.

318 pairs of IFFT unit S ₄, R2 and R6 carry out IFFT and generate the OFDM code element.

Counter-rotating unit 334 makes from the sign-inverted of the R6 of antenna port 5 transmissions.

CDD generation unit 321 is for S ₅, R2 and R6 generate CDD.

322 pairs of IFFT unit S ₅, R2 and R6 carry out IFFT and generate the OFDM code element.

325 pairs of IFFT unit S ₆, R3 and R7 carry out IFFT and generate the OFDM code element.

Counter-rotating unit 335 makes from the sign-inverted of the R7 of antenna port 7 transmissions.

CDD generation unit 328 is for S ₇, R3 and R7 generate CDD.

329 pairs of IFFT unit S ₇, R3 and R7 carry out IFFT and generate the OFDM code element.

Here, for the R4～R7 that only sends when antenna port sends, base station 300 shown in Figure 13 makes the sign-inverted of the RS of any antenna port transmission in two antenna ports that form a virtual-antenna from Figure 12.That is, base station 300 makes the sign-inverted of antenna port 0 and the R4 that the antenna port in antenna port 11 sends of formation virtual-antenna 0 from Figure 12.Similarly, base station 300 makes the sign-inverted of antenna port 2 and the R5 that the antenna port in antenna port 33 sends of formation virtual-antenna 1 from Figure 12.The situation of virtual-antenna 2,3 (antenna port 4～7) is also identical.

Next, the configuration of the RS of expression present embodiment in Figure 14.Moreover, R0 ' expression in Figure 14 sends the resource of R0 from antenna port 0 and antenna port 1, R1 ' expression sends the resource of R1 from antenna port 2 and antenna port 3, R2 ' expression sends the resource of R2 from antenna port 4 and antenna port 5, R3 ' expression sends the resource of R3 from antenna port 6 and antenna port 7.In addition, R4 ' expression sends R4 and sends the resource of the RS of the sign-inverted gained that makes R4 from antenna port 1 from antenna port 0, R5 ' expression sends R5 and sends the resource of the RS of the sign-inverted gained that makes R5 from antenna port 3 from antenna port 2, R6 ' expression sends R6 and sends the resource of the RS of the sign-inverted gained that makes R6 from antenna port 5 from antenna port 4, and R7 ' expression sends R7 and sends the resource of the RS of the sign-inverted gained that makes R7 from antenna port 7 from antenna port 6.

In addition, as shown in figure 14, base station 300 is divided into whole frequency band (subcarrier sequence number 0～23), the LTE terminal (or in the LTE+ terminal of only supporting the 4Tx base station is mail in configuration, transmission frequency band (the subcarrier sequence number 0～11 of the data-signal terminal at 4RS transmission frequency band downlink data receiving signal), hereinafter referred to as " 4RS sends frequency band ") and configuration mail to the transmission frequency band (subcarrier sequence number 12～23 is hereinafter referred to as " 8RS sends frequency band ") of the data-signal of the LTE+ terminal of also supporting the 8Tx base station.In addition, base station 300 can be with the segmentation result of frequency band by broadcast announcement to the LTE+ terminal, also can use downgoing control signal (for example, PDCCH etc.), send with being illustrated in 8RS the information that frequency band sends eight RS, only notify to data-signal and be assigned to the terminal that 8RS sends frequency band.

With with send R0 ' shown in Figure 14～R3 ' from the identical resource (identical timing and same subcarrier) of the R0～R3 (Fig. 2 B) of the 4Tx base station of 3GPP-LTE.In addition, R0 '～R3 ' is configured in all frequency bands (subcarrier sequence number 0～23 shown in Figure 14).In addition, send in frequency band (subcarrier sequence number 12～23) at 8RS shown in Figure 14, except disposing R0～R3, also dispose R4～R7.

In the situation that base station 300 works as virtual 4Tx base station, send from the base station 300 RS with the R0 ' that is disposed at 4RS shown in Figure 14 and sends frequency band～R3 '.That is, when virtual transmission, send the required expense of RS identical with the 4Tx base station.In addition, from antenna port 0 and antenna port 1 with mutually in the same time, same frequency sends R0 ' shown in Figure 14, from antenna port 2 and antenna port 3 with mutually in the same time, same frequency sends R1 ', from antenna port 4 and antenna port 5 with mutually in the same time, same frequency sends R2 ', from antenna port 6 and antenna port 7 with mutually in the same time, same frequency sends R3 '.Thus, because each virtual-antenna can use two wireless transmission unit to send RS, so the transmitted power of the transmitted power of RS and data-signal is 2 times of corresponding transmitted power in the 4Tx base station.Thus, can improve the quality of reception of terminal.

On the other hand, in the situation that base station 300 works as the 8Tx base station, send the R0～R3 of frequency band and only be disposed at R4～R7 that 8RS sends frequency band and send from the base station 300 RS with the 8RS that is disposed at shown in Figure 14.But, as shown in figure 13, although from antenna port 0 and antenna port 1 with mutually in the same time, same frequency sends R4 ', the symbol of the R4 that sends from antenna port 1 is inverted for the R4 from antenna port 0 transmission.The situation of R5 ', R6 ', R7 ' is also identical.

That is, be equivalent in base station shown in Figure 13 300, R0, R1, R2 and R3 are applied (1,1) as the virtual-antenna weight, and R4, R5, R6 and R7 are applied (1 ,-1) with (1,1) quadrature as the virtual-antenna weight.

Next, describe sending data.In base station shown in Figure 12 300, at first the transmission data that send the frequency band transmission with 4RS are mapped on four virtual-antennas 0～3 by map unit 303.Then, for the transmission data that are mapped on each virtual-antenna, apply be applied to R0, R1, R2, R3 on the identical virtual-antenna weight of virtual-antenna weight.On the other hand, in base station shown in Figure 13 300, the transmission data that send the frequency band transmission with 8RS are mapped directly on eight antenna ports by map unit 303.But, because the transmission data that send with 8RS transmission frequency band are mapped on eight antenna ports by map unit 303, so can't apply the virtual-antenna weight.

Next the action of terminal is described.

For example, in the situation that the LTE terminal is measured the downgoing line power that (Measurement) switches or use when searching for new residential quarter, the LTE terminal is used R0 '～R3 '.That is, the LTE terminal is measured respectively the received power of R0 '～R3 ' as the signal strength signal intensity of virtual-antenna 0～3.Then, the LTE terminal feeds back to base station 300 with measurement result.Here, it is four RS that antenna port sends via the 4Tx base station that the LTE terminal need not to differentiate the RS that uses in mensuration, or the 8Tx base station RS that uses virtual-antenna to send.That is, the LTE terminal can not differentiated 4Tx base station and 8Tx base station and measure downgoing line power.In addition, the R0 ' that uses in base station 300 is measured～R3 ' uses respectively the virtual-antenna that is formed by two antenna ports to send, and therefore in the LTE terminal, the density of RS (aggregate power) uprises, and can carry out high-precision mensuration.

In addition, during with 4RS frequency band downlink data receiving signal shown in Figure 14, the LTE terminal uses R0 '～R3 ' to carry out the channel estimating of each antenna port when LTE terminal (or in LTE+ terminal, sending the terminal of frequency band downlink data receiving signal with 4RS).Then, 4 antenna port antenna terminal mapping patterns that the LTE terminal uses four channel estimation values and base station 300 to prenotice receive 300 data-signals that send from the base station.Here, because 300 pairs of base stations virtual-antenna 0～3 applies the virtual-antenna weight, be the fact of eight and downlink data receiving signal so the LTE terminal can not considered the antenna port number of base station 300.

In addition, when 8RS shown in Figure 14 sent frequency band downlink data receiving signal, the LTE+ terminal was by the signal of following calculating separate antenna port 0～7 when the LTE+ terminal, and carried out the channel estimating of each antenna port.

From the signal of antenna port 0=(R0 ' in reception signal+R4 ' in the reception signal)/2

From the signal of antenna port 1=(R0 ' in reception signal-R4 ' in the reception signal)/2

From the signal of antenna port 2=(R1 ' in reception signal+R5 ' in the reception signal)/2

From the signal of antenna port 3=(R1 ' in reception signal-R5 ' in the reception signal)/2

From the signal of antenna port 4=(R2 ' in reception signal+R6 ' in the reception signal)/2

From the signal of antenna port 5=(R2 ' in reception signal-R6 ' in the reception signal)/2

From the signal of antenna port 6=(R3 ' in reception signal+R7 ' in the reception signal)/2

From the signal of antenna port 7=(R3 ' in reception signal-R7 ' in the reception signal)/2

Like this, the LTE+ terminal is used eight channel estimation values and 8 antenna port antenna terminal mapping patterns of antenna port 0～7, receives 300 downlink data signals that send from the base station.

And the LTE+ terminal feeds back to base station 300 with eight channel estimation values of antenna port 0～7 by uplink.Base station 300 is based on feedack, determines should to be applicable to after the transmission of carrying out next time to mail to the antenna terminal mapping pattern of the downlink data of LTE+ terminal.

In addition, by the LTE terminal of the multiplexing applicable virtual-antenna transmission of OFDM and the LTE+ terminal of applicable antenna port transmission, therefore, each terminal switching virtual antenna is sent (Figure 12) in base station 300 and antenna port sends (Figure 13).That is, base station 300 has switch unit, and each terminal switching virtual antenna is sent (Figure 12) to this switch unit and antenna port sends (Figure 13).And the LTE terminal that base station 300 sends for applicable virtual-antenna by structure shown in Figure 12, is mapped in 4RS transmission frequency band shown in Figure 14 RS and data-signal to carry out the virtual-antenna transmission.In addition, the LTE+ terminal that base station 300 sends for applicable antenna port by structure shown in Figure 13, is mapped in 8RS transmission frequency band shown in Figure 14 RS and data-signal to carry out the antenna port transmission.

And the LTE terminal directly uses the RS that sends with the virtual-antenna sending mode to carry out channel estimating.On the other hand, the LTE+ terminal is separated RS for the RS that sends with the antenna port sending mode to each antenna port, and uses the RS after separating to carry out channel estimating.

In the present embodiment, 8Tx uses virtual-antenna for the LTE terminal in the base station, sends thereby use all eight antenna ports to carry out virtual-antenna.Therefore, can effectively utilize eight antenna ports.That is, because the LTE terminal receives identical RS from two antenna ports that form virtual-antenna, so can improve the quality of reception.In addition, by having used the transmission of virtual-antenna, the LTE terminal can not differentiated the antenna port number of base station and mensuration when switching (handover) and searching for new residential quarter.

In addition, in the present embodiment, the 8Tx base station uses eight antenna ports to send the LTE+ terminal of data-signals for being suitable for, and does not use virtual-antenna but uses eight antenna ports to send data-signals.Here, 8Tx only appends configuration RS in the base station in the frequency band of the data that have been configured the LTE+ terminal of supporting the 8RS receive mode is sent, therefore, the expense of RS can be suppressed at Min..In addition, the LTE+ terminal can be separated into the RS that receives respectively the RS of eight antenna ports.Thus, wish the LTE terminal that virtual-antenna sends and wish that LTE+ terminal that antenna port sends can coexist in the residential quarter that the base station covers.

In addition, the base station 300 in Figure 12 and Figure 13 also can not be equipped with the CDD generation unit.

Radio communication device of the present invention comprises: virtual-antenna is formed by a plurality of antenna ports; And the counter-rotating unit, make any the sign-inverted from the reference signal that each port of described a plurality of antenna ports sends.

Radio communication device of the present invention also comprises: switch unit, use a plurality of described virtual-antennas, the switching virtual antenna sends with antenna port and sends, described virtual-antenna is sent as the transmission that data-signal is mapped to respectively a plurality of described virtual-antennas, and described antenna port is sent as the transmission that data-signal is mapped to respectively described a plurality of antenna ports.

In radio communication device of the present invention, described counter-rotating unit makes any the sign-inverted from the reference signal that each port of described a plurality of antenna ports sends in the frequency band that sends broadcast channel signal.

In radio communication device of the present invention, described counter-rotating unit makes only to be disposed at and carries out data-signal is mapped to respectively the reference signal of the frequency band that the antenna port of described a plurality of antenna ports sends and any the sign-inverted from the described reference signal that each ports of described a plurality of antenna ports sends.

Wireless communications method of the present invention is used for comprising the radio communication device of the virtual-antenna that is formed by a plurality of antenna ports, makes any the sign-inverted from the reference signal of each port transmission of described a plurality of antenna ports.

Above, embodiments of the present invention are illustrated.

In addition, terminal is also sometimes referred to as UE, and the base station is also sometimes referred to as Node B, and subcarrier is also sometimes referred to as tone (tone).In addition, CP is also sometimes referred to as and protects interval (Guard Interval:GI).

In addition, the method for changing between frequency domain and time domain is not limited to IFFT, FFT.

In addition, the present invention is not only applicable to base station and terminal, and applicable to all radio communication devices.

In addition, in the above-described embodiment, for example understand with hardware to consist of situation of the present invention, but the present invention also can realize by software.

In addition, the LSI that each functional block of using in the explanation of above-mentioned execution mode is used as integrated circuit usually realizes.These functional blocks both can be integrated into a chip individually, were integrated into a chip with also can comprising part or all.Although referred to herein as LSI, according to the difference of degree of integration, also can be called as IC, system LSI, super large LSI or especially big LSI.

In addition, realize that the method for integrated circuit is not limited only to LSI, also can realize with special circuit or general processor.Also can use can programming after LSI makes FPGA (Field Programmable Gate Array: field programmable gate array), the perhaps reconfigurable processor of the connection of the circuit unit of restructural LSI inside and setting.

Moreover, along with the progress of semiconductor technology or the appearance of other technology of derivation thereupon, if there is the new technology of the integrated circuit that can substitute LSI, certainly can utilize this new technology to carry out the integrated of functional block.Also exist the possibility of applicable biotechnology etc.

The disclosure of specification, accompanying drawing and specification digest that the Japanese patent application that No. the 2007-213077th, the Japanese patent application that on August 17th, 2007 proposed and on June 23rd, 2008 propose comprises for No. 2008-163032 all is incorporated in the application.

Industrial applicibility

The present invention can be applicable to mobile communication system etc.

Claims (16)

1. base station apparatus comprises:

Transmitting element from a plurality of antenna ports, sends the 1st reference signal with a plurality of the 1st resource elements, and sends 2nd reference signal different from described the 1st reference signal with a plurality of the 2nd resource elements of the number that is less than described a plurality of the 1st resource elements,

Use either party or described the 1st reference signal of described the 1st reference signal and described the 2nd reference signal and described the 2nd reference signal both, will whether carry out channel quality with terminal and measure the antenna port number that is associated and be set in described terminal.

2. base station apparatus as claimed in claim 1,

Described transmitting element is that send with the part antenna from described a plurality of antenna ports, any the sign-inverted in identical described the 2nd reference signal sends.

3. base station apparatus as claimed in claim 1,

Described the 2nd reference signal comprises two same components, one side of described two same components be multiplied by 1 and the 1st antenna from described a plurality of antenna ports send, the opposing party of described two same components be multiplied by-1 and the 2nd antenna of the 1st antenna from be different from described a plurality of antenna port send.

4. base station apparatus as claimed in claim 1,

Described the 1st reference signal is used for the channel quality estimation of downgoing line and the mensuration of downgoing line power, and described the 2nd reference signal is used for the channel quality estimation of downgoing line.

5. base station apparatus as claimed in claim 1,

Antenna port number when using described the 1st reference signal to carry out channel quality estimation is for being less than or equal to 4, and the antenna port number when using described the 2nd reference signal to carry out channel quality estimation is 8.

6. base station apparatus as claimed in claim 1,

Be used for the number of resource element of each antenna port of described the 1st reference signal greater than the number of the resource element of each antenna port of described the 2nd reference signal.

7. terminal installation comprises:

Receiving element, receive the 1st reference signal of using a plurality of antenna ports to send from base station apparatus with the 1st resource element, and receive with the 2nd resource element of the number that is less than described a plurality of the 1st reference signals 2nd reference signal different from described the 1st reference signal of using a plurality of antenna ports to send from base station apparatus; And

Estimation unit based on the antenna port number of setting for our device, uses either party in both of described the 1st reference signal and described the 2nd reference signal to carry out channel quality estimation.

8. terminal installation as claimed in claim 7,

The 2nd reference signal that described receiving element receives that part antenna from described a plurality of antenna ports is that send, any the symbol in identical described the 2nd reference signal is inverted transmission.

9. terminal installation as claimed in claim 7,

Described the 2nd reference signal comprises two same components, one side of described two same components be multiplied by 1 and the 1st antenna from described a plurality of antenna ports send, the opposing party of described two same components be multiplied by-1 and the 2nd antenna of the 1st antenna from be different from described a plurality of antenna port send.

10. terminal installation as claimed in claim 7,

Described the 1st reference signal is used for the mensuration of described channel quality estimation and downgoing line power, and described the 2nd reference signal is used for described channel quality estimation.

11. terminal installation as claimed in claim 7,

Antenna port number when using described the 1st reference signal to carry out channel quality estimation is for being less than or equal to 4, and the antenna port number when using described the 2nd reference signal to carry out channel quality estimation is 8.

12. terminal installation as claimed in claim 7,

Be used for the number of resource element of each antenna port of described the 1st reference signal greater than the number of the resource element of each antenna port of described the 2nd reference signal.

13. sending method comprises:

Forwarding step from a plurality of antenna ports, sends the 1st reference signal with a plurality of the 1st resource elements, and sends 2nd reference signal different from described the 1st reference signal with a plurality of the 2nd resource elements of the number that is less than described a plurality of the 1st resource elements; And

Set step, uses described the 1st reference signal and described the 2nd reference signal in both either party or both, will whether carry out the antenna port number that channel quality mensuration is associated with terminal and be set in described terminal.

14. method of reseptance comprises:

Receiving step, receive the 1st reference signal of using a plurality of antenna ports to send from base station apparatus with the 1st resource element, and receive with the 2nd resource element of the number that is less than described a plurality of the 1st reference signals 2nd reference signal different from described the 1st reference signal of using a plurality of antenna ports to send from base station apparatus; And

Estimating step based on the antenna port number of setting for terminal installation, uses either party in both of described the 1st reference signal and described the 2nd reference signal to carry out channel quality estimation.

15. integrated circuit, it controls following the processing:

From a plurality of antenna ports, send the 1st reference signal with a plurality of the 1st resource elements, and send 2nd reference signal different from described the 1st reference signal with a plurality of the 2nd resource elements of the number that is less than described a plurality of the 1st resource elements; And

Use described the 1st reference signal and described the 2nd reference signal in both either party or both, will whether carry out channel quality with terminal and measure the antenna port number that is associated and be set in described terminal.

16. integrated circuit, it controls following the processing:

Receive the 1st reference signal of using a plurality of antenna ports to send from base station apparatus with the 1st resource element, and receive 2nd reference signal different from described the 1st reference signal with the 2nd resource element of the number that is less than described a plurality of the 1st reference signals; And

Based on the antenna port number of setting for our device, use either party in both of described the 1st reference signal and described the 2nd reference signal to carry out channel quality estimation.

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